[Haskell] Optimistic Evaluation?

[Ian Lynagh]

On Sun, Aug 27, 2006 at 05:51:34PM -0400, Lajos Nagy wrote:
> 
> I remember once reading a paper by SPJ about Optimistic Evaluation that
> is somewhere between lazy and strict.  If I remember correctly, they even
> implemented it in GHC.  Now, it seems that current version of GHC doesn't
> support optimistic evaluation (not even as an optional feature), so my 
> question
> is: what happened to OE?

It was only ever in a branch of ghc 5.something.

> Was it that it seemed like a good idea on paper
> but not in reality?  Or was it too costly to maintain?  Or it didn't deliver
> the goods it promised?  I'm just curious.

My understanding is that the benefit it gave didn't make up for the
increased complexity of GHC's source code.


Thanks
Ian